With the hotfixes released in August 2008, Microsoft is significantly improving the capability for Office Communications Server 2007 to exchange calls with SIP-based IP-PBX, in particular from Cisco. As a consequence, Microsoft now supports OCS deployments in Direct SIP with IP-PBX between Office Communications Server and specific versions of Cisco Call Manager.
This change gives administrators the possibility to set up Office Communications Server so that it can directly interoperate with IP-PBX using E.164 globally routable telephone numbers without RFC3966’s mandated “+” prefix. Additionally, Office Communications Server will now be able to interoperate with IP-PBX within a private dialing plan, exchanging locally routable private numbers…..
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